The prior art teaches many systems for setting the fuze of a bomb or artillery shell. For example, the patents to Deloraine U.S. Pat. No. 2,557,949, Watt U.S. Pat. No. 2,555,384, and Schuler et al. U.S. Pat. No. 1,739,921 set the fuze of an artillery shell as it leaves the muzzle of the gun by adjusting the magnitude of a magnetic field through which the shell is passing. The White, Jr. et al. U.S. Pat. No. 3,211,057 shows the setting of a fuze in a bomb by means of a transformer arrangement in which one-half of the transformer is located within the bomb and the other half is located on the aircraft. None of the prior art of which I am aware provides a digital fuze having a plurality of binary bit positions, each of which is simultaneously set as the shell exits from the muzzle of the gun.
In accordance with this invention a binary code representing the time-to-go delay interval is set into the fuze by simultaneously transmitting a plurality of discrete frequency signals, each representing a digit in a binary coded command. The communication link comprises the magnetic field of a coil through which the receiver of the fuze physically passes. The system uses binary information which is serially inserted into a binary counter but which is read out in parallel so that all of the bit positions in the fuze are simultaneously set as the fuze passes through the coil after the projectile is fired, but before it leaves the muzzle of the gun.